The present invention relates to a buffer for supporting an elevator car and/or for supporting a counterweight for the elevator car, and an elevator installation with such a buffer.
Elevator installations are usually provided with one or more buffers which are arranged at the shaft floor of an elevator shaft in order to stop the elevator car when overrunning the lowermost stopping position in the elevator shaft in the downward direction and/or when overrunning the uppermost stopping position in the elevator shaft in the upward direction after transit of a predetermined travel path. This buffer is usually seated below the elevator car and/or the counterweight.
In order to prevent overrunning of an uppermost stopping position in the elevator shaft in the upward direction at the latest after transiting a predetermined travel path, buffers can also be arranged at the shaft head above the elevator car. Due to the fact that such buffers have to be arranged at the shaft floor and shaft head directly below or above the elevator car, a specific space requirement results. The shaft head or the shaft floor can therefore only be conditionally utilized for other purposes. In the case of elevator installations without a shaft pit, such a standard arrangement of a buffer is not possible, since little space is present underneath the elevator car.
An elevator installation with an elevator shaft, a vertically movable elevator car with counterweight and with buffers is described in PCT Patent Application WO 00/64798-A1, wherein the buffer is disposed not below the elevator car, but near the elevator car at the shaft floor. The elevator car is provided with brackets that impinge on the buffer if an overrun situation arises, i.e. if the elevator car goes beyond the lowermost stopping position at the lowermost floor in the downward direction. The elevator car is thereby braked and stopped in a short distance above the shaft floor. An overrun protection against overrunning the uppermost stopping position of the elevator car in the upward direction is not proposed in this PCT patent application. The elevator installation has a shaft without a pit. A possibility of creating temporary zones of protection for carrying out of maintenance and repair operations in the elevator shaft at the shaft floor and/or at the shaft head is not disclosed.